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From: cnh5730@maraba.tamu.edu
Newsgroups: comp.sys.next
Subject: Re: Help, please, on making connections in IB
Message-ID: <CNH5730.91Apr19190110@maraba.tamu.edu>
Date: 20 Apr 91 00:01:10 GMT
References: <2524@fornax.UUCP> <LIBERTE.91Apr19145552@babbage.ncsa.uiuc.edu>
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In article <LIBERTE.91Apr19145552@babbage.ncsa.uiuc.edu> liberte@ncsa.uiuc.edu (Daniel LaLiberte) writes:
   In article <2524@fornax.UUCP> mcdonald@fornax.UUCP (Ken Mcdonald) writes:
   >  The first problem is that I can't even create an object of 
   >  class EntryField
   >  in Interface Builder.  

   You're right, you can't instantiate your subclass, unless it is a
   subclass of Object.  I dont know why this restriction exists, but
   there it is.  

Here are the classes which I can determine that IB will allow you to
instantiate:
1) Object
2) UserCreatedSubclassesOf:Object
3) List:Object
4) HashTable:Object
5) Sound:Object
6) Storage:Object
7) NXStringTable:HashTable:Object

so clearly IB knows how to instantiate some of its (sub)classes but not others.